/* s_vcsa.c -- LZO packer

   This file is part of the LZO real-time data compression package.

   Copyright (C) 1998 Markus Franz Xaver Johannes Oberhumer
   Copyright (C) 1997 Markus Franz Xaver Johannes Oberhumer
   Copyright (C) 1996 Markus Franz Xaver Johannes Oberhumer

   The LZO library and packer is free software; you can redistribute it
   and/or modify it under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2 of
   the License, or (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; see the file COPYING.
   If not, write to the Free Software Foundation, Inc.,
   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

   Markus F.X.J. Oberhumer
   markus.oberhumer@jk.uni-linz.ac.at
 */


#include "lzopack.h"

#if defined(USE_SCREEN) && defined(USE_SCREEN_VCSA)

#include "screen.h"

#define mask_fg	0x0f
#define mask_bg	0xf0


/*************************************************************************
// direct screen access ( /dev/vcsaNN )
**************************************************************************/

#include <sys/ioctl.h>
#include <termios.h>
#if defined(__linux__)
#  include <linux/kd.h>
#  include <linux/kdev_t.h>
#  include <linux/major.h>
#endif


struct screen_data_t
{
	int fd;
	int mode;
	int page;
	int cols;
	int rows;
	int cursor_x;
	int cursor_y;
	unsigned char attr;
	unsigned char init_attr;
	unsigned char map[256];
	unsigned short empty_line[256];
};



static void refresh(screen_t *this)
{
	UNUSED(this);
}


static __inline__
unsigned short make_cell(screen_t *this, int ch, int attr)
{
	return ((attr & 0xff) << 8) | (this->data->map[ch & 0xff] & 0xff);
}


static int getMode(const screen_t *this)
{
	return this->data->mode;
}


static int getPage(const screen_t *this)
{
	return this->data->page;
}


static int getRows(const screen_t *this)
{
	return this->data->rows;
}


static int getCols(const screen_t *this)
{
	return this->data->cols;
}


static int getFg(const screen_t *this)
{
	return this->data->attr & mask_fg;
}


static int getBg(const screen_t *this)
{
	return this->data->attr & mask_bg;
}


static void setFg(screen_t *this, int fg)
{
	this->data->attr = (this->data->attr & mask_bg) | (fg & mask_fg);
}


static void setBg(screen_t *this, int bg)
{
	this->data->attr = (this->data->attr & mask_fg) | (bg & mask_bg);
}


/* private */
static int gotoxy(screen_t *this, int x, int y)
{
	if (x >= 0 && y >= 0 && x < this->data->cols && y < this->data->rows)
	{
		if (lseek(this->data->fd, 4 + (x + y * this->data->cols) * 2, SEEK_SET) != -1)
		{
			return 0;
		}
	}
	return -1;
}


static void setCursor(screen_t *this, int x, int y)
{
	if (gotoxy(this,x,y) == 0)
	{
		unsigned char b[2] = { x, y };
		if (lseek(this->data->fd, 2, SEEK_SET) != -1)
			write(this->data->fd, b, 2);
       	this->data->cursor_x = x;
       	this->data->cursor_y = y;
	}
}


static void getCursor(const screen_t *this, int *x, int *y)
{
	if (x)
		*x = this->data->cursor_x;
	if (y)
		*y = this->data->cursor_y;
}


static void putCharAttr(screen_t *this, int ch, int attr, int x, int y)
{
	unsigned short a = make_cell(this,ch,attr);

	if (gotoxy(this,x,y) == 0)
		write(this->data->fd, &a, 2);
}


static void putChar(screen_t *this, int ch, int x, int y)
{
	putCharAttr(this,ch,this->data->attr,x,y);
}


static void putStringAttr(screen_t *this, const char *s, int attr, int x, int y)
{
	while (*s)
		putCharAttr(this,*s++,attr,x++,y);
}


static void putString(screen_t *this, const char *s, int x, int y)
{
	putStringAttr(this,s,this->data->attr,x,y);
}


/* private */
static void getChar(screen_t *this, int *ch, int *attr, int x, int y)
{
	unsigned short a;

	if (gotoxy(this,x,y) == 0 && read(this->data->fd, &a, 2) == 2)
	{
		if (ch)
			*ch = a & 0xff;
		if (attr)
			*attr = (a >> 8) & 0xff;
	}
}


/* private */
static int init_scrnmap(screen_t *this, int fd)
{
	int scrnmap_done = 0;
	int i;

#if 1 && defined(GIO_UNISCRNMAP) && defined(E_TABSZ)
	if (!scrnmap_done)
	{
		unsigned short scrnmap[E_TABSZ];
		if (ioctl(fd, GIO_UNISCRNMAP, scrnmap) == 0)
		{
			for (i = 0; i < E_TABSZ; i++)
				this->data->map[scrnmap[i] & 0xff] = i;
			scrnmap_done = 1;
		}
	}
#endif
#if 1 && defined(GIO_SCRNMAP) && defined(E_TABSZ)
	if (!scrnmap_done)
	{
		unsigned char scrnmap[E_TABSZ];
		if (ioctl(fd, GIO_SCRNMAP, scrnmap) == 0)
		{
			for (i = 0; i < E_TABSZ; i++)
				this->data->map[scrnmap[i] & 0xff] = i;
			scrnmap_done = 1;
		}
	}
#endif

	return scrnmap_done;
}


static int init(screen_t *this, int fd)
{
	struct stat st;

	if (!this || !this->data)
		return -1;

	this->data->fd = -1;
	this->data->mode = -1;
	this->data->page = 0;

	if (fd < 0 || !isatty(fd))
		return -1;
	if (fstat(fd,&st) != 0)
		return -1;

	/* check if we are running in a virtual console */
#if defined(MINOR) && defined(MAJOR) && defined(TTY_MAJOR)
	if (MAJOR(st.st_rdev) == TTY_MAJOR)
	{
		char vc_name[32];
		unsigned char vc_data[4];
		int i;
		int attr;
		unsigned short a;

   		sprintf(vc_name, "/dev/vcsa%d", (int) MINOR(st.st_rdev));
		this->data->fd = open(vc_name, O_RDWR);
		if (this->data->fd != -1)
		{
   			if (read(this->data->fd, vc_data, 4) == 4)
			{
				this->data->mode = 3;
				this->data->rows = vc_data[0];
				this->data->cols = vc_data[1];
				this->data->cursor_x = vc_data[2];
				this->data->cursor_y = vc_data[3];

				for (i = 0; i < 256; i++)
					this->data->map[i] = i;
				i = init_scrnmap(this,this->data->fd) ||
				    init_scrnmap(this,STDIN_FILENO);

				getChar(this,NULL,&attr,this->data->cursor_x,this->data->cursor_y);
				this->data->init_attr = attr;
				this->data->attr = attr;
				a = make_cell(this,' ',attr);
				for (i = 0; i < 256; i++)
					this->data->empty_line[i] = a;
			}
			else
			{
				close(this->data->fd);
				this->data->fd = -1;
			}
		}
	}
#endif

	if (this->data->mode < 0)
		return -1;

	return 0;
}


static void finalize(screen_t *this)
{
	if (this->data->fd != -1)
		(void) close(this->data->fd);
}


static void updateLineN(screen_t *this, const void *line, int y, int len)
{
	if (len > 0 && len <= 2*this->data->cols && gotoxy(this,0,y) == 0)
	{
		int i;
		unsigned char new_line[len];
		unsigned char *l1 = new_line;
		const unsigned char *l2 = line;

		for (i = 0; i < len; i += 2)
		{
			*l1++ = *l2++;
			*l1++ = this->data->map[*l2++];
		}
		write(this->data->fd, new_line, len);
	}
}


static void clearLine(screen_t *this, int y)
{
	if (gotoxy(this,0,y) == 0)
		write(this->data->fd, this->data->empty_line, 2*this->data->cols);
}


static void clear(screen_t *this)
{
	int y;

	for (y = 0; y < this->data->rows; y++)
		clearLine(this,y);
}


static int scrollUp(screen_t *this, int lines)
{
	int sr = this->data->rows;
	int sc = this->data->cols;
	int y;

	if (lines <= 0)
		return 0;
	if (lines >= sr)
		clear(this);
	else
	{
		unsigned short buf[	(sr-lines)*sc ];

		gotoxy(this,0,lines);
		read(this->data->fd, buf, sizeof(buf));
		gotoxy(this,0,0);
		write(this->data->fd, buf, sizeof(buf));

		for (y = sr - lines; y < sr; y++)
			clearLine(this,y);
	}
	return lines;
}


static int getCursorShape(const screen_t *this)
{
	UNUSED(this);
	return 0;
}


static void setCursorShape(screen_t *this, int shape)
{
	UNUSED(this);
	UNUSED(shape);
}


static int kbhit(screen_t *this)
{
	const int fd = STDIN_FILENO;
	const unsigned long usec = 0;
	struct timeval tv;
	fd_set fds;

	UNUSED(this);
	FD_ZERO(&fds);
	FD_SET(fd, &fds);
   	tv.tv_sec  = usec / 1000000;
	tv.tv_usec = usec % 1000000;
	return (select(fd + 1, &fds, NULL, NULL, &tv) > 0);
}


static int intro(screen_t *this, void (*show_frames)(screen_t *) )
{
	int shape;
	struct termios term_old, term_new;
	int term_r;

	if ((this->data->init_attr & mask_bg) != BG_BLACK)
		return 0;

	term_r = tcgetattr(STDIN_FILENO, &term_old);
	if (term_r == 0)
	{
		term_new = term_old;
		term_new.c_lflag &= ~(ISIG | ICANON | ECHO);
		tcsetattr(STDIN_FILENO, TCSANOW, &term_new);
	}

	shape = getCursorShape(this);
	setCursorShape(this,0x2000);
	show_frames(this);
	if (this->data->rows > 24)
		setCursor(this,this->data->cursor_x,this->data->cursor_y+1);
	setCursorShape(this,shape);

	while (kbhit(this))
		(void) getchar();
	if (term_r == 0)
		tcsetattr(STDIN_FILENO, TCSANOW, &term_old);

	return 1;
}


static const screen_t driver =
{
	sobject_destroy,
	finalize,
	init,
	refresh,
	getMode,
	getPage,
	getRows,
	getCols,
	getFg,
	getBg,
	getCursor,
	getCursorShape,
	setFg,
	setBg,
	setCursor,
	setCursorShape,
	putChar,
	putCharAttr,
	putString,
	putStringAttr,
	clear,
	clearLine,
	updateLineN,
	scrollUp,
	kbhit,
	intro,
	(struct screen_data_t *) 0
};


/* public constructor */
screen_t *screen_vcsa_construct(void)
{
	return sobject_construct(&driver,sizeof(*driver.data));
}


#endif /* defined(USE_SCREEN) && defined(USE_SCREEN_VCSA) */


/*
vi:ts=4
*/